Real-Time Scheduling and Analysis of OpenMP Task Systems with Tied Tasks

Jinghao Sun, Nan Guan, Yang Wang, Qingqiang He, Wang Yi

Research output: Chapter in book / Conference proceedingConference article published in proceeding or bookAcademic researchpeer-review

15 Citations (Scopus)


OpenMP is a promising framework for developing parallel real-time software on multi-cores. Although similar to the DAG task model, OpenMP task systems are significantly more difficult to analyze due to constraints posed by the OpenMP specification. An important feature in OpenMP is tied tasks, which must execute on the same thread during the whole life cycle. Although tied tasks enjoy benefits in simplicity and efficiency, it was considered to be not suitable to real-time systems due to its complex behavior. In this paper, we study the realtime scheduling and analysis of OpenMP task systems with tied tasks. First, we show that under the existing scheduling algorithms in OpenMP, tied tasks indeed may lead to extremely bad timing behaviors where the parallel workload is sequentially executed completely. To solve this problem, we proposed a new scheduling algorithm and developed two response time bounds for it, with different trade-off between simplicity and analysis precision. Experiments with both randomly generated OpenMP task systems and realistic OpenMP programs show that the response time bounds obtained by our approach for tied task systems are very close to that of untied tasks.
Original languageEnglish
Title of host publicationProceedings - 2017 IEEE Real-Time Systems Symposium, RTSS 2017
Number of pages12
ISBN (Electronic)9781538614143
Publication statusPublished - 31 Jan 2018
Event38th IEEE Real-Time Systems Symposium, RTSS 2017 - Paris, France
Duration: 5 Oct 20178 Oct 2017

Publication series

NameProceedings - Real-Time Systems Symposium
ISSN (Print)1052-8725


Conference38th IEEE Real-Time Systems Symposium, RTSS 2017


  • openmp
  • parallel-software
  • real-time-systems
  • response-time-analysis
  • tied-task

ASJC Scopus subject areas

  • Software
  • Hardware and Architecture
  • Computer Networks and Communications

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